Move images around

client/cursor.js

@@ -1,48 +1,73 @@
 function on_down(e) {
+    const x = Math.round((e.clientX + storage.canvas.offset_x) / storage.canvas.zoom);
+    const y = Math.round((e.clientY + storage.canvas.offset_y) / storage.canvas.zoom);
+
     if (e.button === 1) {
-        elements.canvas0.classList.add('moving');
         storage.state.moving = true;
         storage.state.mousedown = true;
         return;
     }
 
-    if (e.button != 0) {
+    if (e.button === 2) {
+        const image_hit = image_at(x, y);
+        activate_image(image_hit);
+        e.preventDefault();
         return;
     }
 
-    if (storage.state.moving) {
-        storage.state.mousedown = true;
-        return;
-    }
+    if (e.button === 0) {
+        const image_hit = image_at(x, y);
 
-    const x = Math.round((e.clientX + storage.canvas.offset_x) / storage.canvas.zoom);
-    const y = Math.round((e.clientY + storage.canvas.offset_y) / storage.canvas.zoom);
+        if (elements.active_image !== null && image_hit !== null) {
+            storage.state.moving_image = true;
+            return;
+        }
 
-    storage.state.drawing = true;
+        if (storage.state.moving) {
+            storage.state.mousedown = true;
+            return;
+        }
 
-    if (storage.ctx1.lineWidth !== storage.cursor.width) {
-        storage.ctx1.lineWidth = storage.cursor.width;
-    }
+        storage.state.drawing = true;
 
-    storage.cursor.x = x;
-    storage.cursor.y = y;
+        if (storage.ctx1.lineWidth !== storage.cursor.width) {
+            storage.ctx1.lineWidth = storage.cursor.width;
+        }
 
-    const predraw = predraw_event(x, y);
-    storage.current_stroke.push(predraw);
+        storage.cursor.x = x;
+        storage.cursor.y = y;
 
-    fire_event(predraw);
+        const predraw = predraw_event(x, y);
+        storage.current_stroke.push(predraw);
+
+        fire_event(predraw);
+    }
 }
 
 function on_move(e) {
     const last_x = storage.cursor.x;
     const last_y = storage.cursor.y;
 
-    const x = storage.cursor.x = Math.round((e.clientX + storage.canvas.offset_x) / storage.canvas.zoom);
-    const y = storage.cursor.y = Math.round((e.clientY + storage.canvas.offset_y) / storage.canvas.zoom);
+    const x = storage.cursor.x = Math.max(Math.round((e.clientX + storage.canvas.offset_x) / storage.canvas.zoom), 0);
+    const y = storage.cursor.y = Math.max(Math.round((e.clientY + storage.canvas.offset_y) / storage.canvas.zoom), 0);
 
     const old_offset_x = storage.canvas.offset_x;
     const old_offset_y = storage.canvas.offset_y;
 
+    if (elements.active_image && storage.state.moving_image) {
+        const dx = Math.round(e.movementX / storage.canvas.zoom);
+        const dy = Math.round(e.movementY / storage.canvas.zoom);
+
+        const image_id = elements.active_image.getAttribute('data-image-id');
+
+        const ix = storage.images[image_id].x += dx;
+        const iy = storage.images[image_id].y += dy;
+
+        elements.active_image.style.transform = `translate(${ix}px, ${iy}px)`;
+
+        return;
+    }
+
     if (storage.state.drawing) {
         const width = storage.cursor.width;
 
@@ -75,10 +100,18 @@ function on_move(e) {
 }
 
 async function on_up(e) {
+    if (storage.state.moving_image && e.button === 0) {
+        storage.state.moving_image = false;
+        const image_id = elements.active_image.getAttribute('data-image-id');
+        const position = storage.images[image_id];
+        const event = image_move_event(image_id, position.x, position.y);
+        await queue_event(event);
+        return;
+    }
+
     if (storage.state.moving && (e.button === 1 || e.button === 0)) {
         storage.state.mousedown = false;
         if (!storage.state.spacedown) {
-            elements.canvas0.classList.remove('moving');
             storage.state.moving = false;
             return;
         }
@@ -95,7 +128,6 @@ async function on_up(e) {
 
 function on_keydown(e) {
     if (e.code === 'Space' && !storage.state.drawing) {
-        elements.canvas0.classList.add('moving');
         storage.state.moving = true;
         storage.state.spacedown = true;
         return;
@@ -110,7 +142,6 @@ function on_keydown(e) {
 
 function on_keyup(e) {
     if (e.code === 'Space' && storage.state.moving) {
-        elements.canvas0.classList.remove('moving');
         storage.state.moving = false;
         storage.state.spacedown = false;
     }   
@@ -118,7 +149,6 @@ function on_keyup(e) {
 
 function on_leave(e) {
     if (storage.state.moving) {
-        elements.canvas0.classList.remove('moving');
         storage.state.moving = false;
         storage.state.holding = false;
         return;

client/default.css

@@ -9,23 +9,19 @@ html, body {
 }
 
 .canvas {
-    cursor: crosshair;
     position: absolute;
     top: 0;
     left: 0;
     opacity: 1;
     transition: opacity .2s;
     transform-origin: top left;
+    pointer-events: none;
 }
 
 .canvas.white {
     opacity: 0;
 }
 
-.canvas.moving {
-    cursor: move;
-}
-
 #canvas-images {
     z-index: 0;
 } 
@@ -38,7 +34,6 @@ html, body {
 
 #canvas1 {
     z-index: 2;
-    pointer-events: none;
     opacity: 0.3;
 }
 
@@ -90,5 +85,12 @@ html, body {
 
 .floating-image {
     position: absolute;
-    pointer-events: none;
+    user-drag: none;
+    user-select: none;
+}
+
+.floating-image.activated {
+    outline: 5px solid #5286ff;
+    z-index: 999999 !important;
+    cursor: grab;
 }

client/draw.js

@@ -55,11 +55,6 @@ function redraw_region(bbox) {
             if (stroke_intersects_region(event.points, bbox)) {
                 draw_stroke(event);
             }
-        } else if (event.type === EVENT.IMAGE && !event.deleted) {
-            const image_bbox = bitmap_bbox(event);
-            if (rectangles_intersect(image_bbox, bbox)) {
-                storage.ctx0.drawImage(event.bitmap, image_bbox.xmin, image_bbox.ymin);
-            }
         }
     }
 

client/index.js

@@ -9,6 +9,7 @@ const EVENT = Object.freeze({
     UNDO: 30,
     REDO: 31,
     IMAGE: 40,
+    IMAGE_MOVE: 41,
 });
 
 const MESSAGE = Object.freeze({
@@ -31,6 +32,7 @@ const storage = {
     'state': {
         'drawing': false,
         'moving': false,
+        'moving_image': false,
         'mousedown': false,
         'spacedown': false,
     },
@@ -51,6 +53,8 @@ const storage = {
     'max_zoom': 4,
     'min_zoom': 0.2,
 
+    'images': {},
+
     'canvas': {
         'zoom': 1,
         'width': 4096,
@@ -70,6 +74,7 @@ const elements = {
     'cursor': null,
     'canvas0': null,
     'canvas1': null,
+    'active_image': null,
 };
 
 function event_size(event) {
@@ -91,7 +96,8 @@ function event_size(event) {
             break;
         }
 
-        case EVENT.IMAGE: {
+        case EVENT.IMAGE:
+        case EVENT.IMAGE_MOVE: {
             size += 4 + 2 + 2; // file id + x + y
             break;
         }
@@ -110,6 +116,53 @@ function move_canvas() {
     elements.images.style.transform = `translate(${-storage.canvas.offset_x}px, ${-storage.canvas.offset_y}px) scale(${storage.canvas.zoom})`;    
 }
 
+function image_at(x, y) {
+    let image_hit = null;
+
+    for (let i = storage.events.length - 1; i >= 0; --i) {
+        if (!storage.events[i].deleted && storage.events[i].type === EVENT.IMAGE) {
+            const event = storage.events[i];
+            const item = document.querySelector(`img[data-image-id="${event.image_id}"]`);
+            if (item) {
+                const left = storage.images[event.image_id].x;
+                const right = left + item.width;
+                const top = storage.images[event.image_id].y;
+                const bottom = top + item.height;
+                if (left <= x && x <= right && top <= y && y <= bottom) {
+                    return item;
+                }
+            }
+        }
+    }
+
+    return null;
+}
+
+function activate_image(item) {
+    if (item === null) {
+        elements.canvas1.classList.remove('disabled');
+        if (elements.active_image) {
+            elements.active_image.classList.remove('activated');
+            elements.active_image = null;
+        }        
+        return;
+    }
+
+    elements.canvas1.classList.add('disabled');
+
+    if (elements.active_image) {
+        if (elements.active_image === item) {
+            return;
+        }
+
+        elements.active_image.classList.remove('activated');
+    }
+
+    elements.active_image = item;
+
+    item.classList.add('activated');
+}
+
 function predraw_event(x, y) {
     return {
         'type': EVENT.PREDRAW,
@@ -144,6 +197,15 @@ function image_event(image_id, x, y) {
     }
 }
 
+function image_move_event(image_id, x, y) {
+    return {
+        'type': EVENT.IMAGE_MOVE,
+        'image_id': image_id,
+        'x': x,
+        'y': y,
+    }
+}
+
 function main() {
     const url = new URL(window.location.href);
     const parts = url.pathname.split('/');
@@ -183,11 +245,12 @@ function main() {
     window.addEventListener('pointermove', on_move)
     window.addEventListener('pointerup', on_up);
     window.addEventListener('pointercancel', on_up);
-    window.addEventListener('touchstart', (e) => e.preventDefault());
     window.addEventListener('keydown', on_keydown);
     window.addEventListener('keyup', on_keyup);
     window.addEventListener('resize', on_resize);
     window.addEventListener('wheel', on_wheel);
+    window.addEventListener('touchstart', cancel);
+    window.addEventListener('contextmenu', cancel);
 
     elements.brush_color.addEventListener('input', update_brush);
     elements.brush_width.addEventListener('input', update_brush);

client/recv.js

@@ -71,7 +71,8 @@ function des_event(d) {
             break;
         }
 
-        case EVENT.IMAGE: {
+        case EVENT.IMAGE:
+        case EVENT.IMAGE_MOVE: {
             event.image_id = des_u32(d);
             event.x = des_u16(d);
             event.y = des_u16(d);
@@ -127,13 +128,13 @@ async function handle_event(event) {
                 const other_event = storage.events[i];
                 if (other_event.type === EVENT.STROKE && other_event.user_id === event.user_id && !other_event.deleted) {
                     other_event.deleted = true;
-                    // const stats = stroke_stats(other_event.points, storage.cursor.width);
-                    // redraw_region(stats.bbox);
+                    const stats = stroke_stats(other_event.points, storage.cursor.width);
+                    redraw_region(stats.bbox);
                     break;
                 } else if (other_event.type === EVENT.IMAGE && other_event.user_id === event.user_id && !other_event.deleted) {
-                    // other_event.deleted = true;
-                    // const bbox = bitmap_bbox(other_event);
-                    // redraw_region(bbox);
+                    other_event.deleted = true;
+                    const item = document.querySelector(`img[data-image-id="${other_event.image_id}"]`);
+                    if (item) item.remove();
                     break;
                 }
             }
@@ -144,11 +145,17 @@ async function handle_event(event) {
         case EVENT.IMAGE: {
             const url = config.image_url + event.image_id;
             const item = document.createElement('img');
+            
             item.classList.add('floating-image');
-            item.style.left = `${event.x}px`;
-            item.style.top = `${event.y}px`;
+            item.style['z-index'] = storage.events.length;
+            item.setAttribute('data-image-id', event.image_id);
             item.setAttribute('src', url);
+            item.style.transform = `translate(${event.x}px, ${event.y}px)`;
+
             elements.images.appendChild(item);
+            storage.images[event.image_id] = {
+                'x': event.x, 'y': event.y
+            };
             // const r = await fetch(config.image_url + event.image_id);
             // const blob = await r.blob();
             // const bitmap = await createImageBitmap(blob);
@@ -159,6 +166,16 @@ async function handle_event(event) {
             break;
         }
 
+        case EVENT.IMAGE_MOVE: {
+            const image_id = event.image_id;
+            const item = document.querySelector(`.floating-image[data-image-id="${image_id}"]`);
+            item.style.transform = `translate(${event.x}px, ${event.y}px)`;
+            storage.images[event.image_id] = {
+                'x': event.x, 'y': event.y
+            };
+            break;
+        }
+
         default: { 
             console.error('fuck');
         }

client/send.js

@@ -50,7 +50,8 @@ function ser_event(s, event) {
             break;
         }
 
-        case EVENT.IMAGE: {
+        case EVENT.IMAGE:
+        case EVENT.IMAGE_MOVE: {
             const image_id = parseInt(event.image_id);
             ser_u32(s, image_id);
             ser_u16(s, event.x);
@@ -145,6 +146,7 @@ function push_event(event) {
         }
 
         case EVENT.IMAGE:
+        case EVENT.IMAGE_MOVE:
         case EVENT.UNDO:
         case EVENT.REDO: {
             storage.queue.push(event);

server/deserializer.js

@@ -55,7 +55,8 @@ export function event(d) {
             break;
         }
 
-        case EVENT.IMAGE: {
+        case EVENT.IMAGE: 
+        case EVENT.IMAGE_MOVE: {
             event.image_id = u32(d);
             event.x = u16(d);
             event.y = u16(d);

server/enums.js

@@ -10,6 +10,7 @@ export const EVENT = Object.freeze({
     UNDO: 30,
     REDO: 31,
     IMAGE: 40,
+    IMAGE_MOVE: 41,
 });
 
 export const MESSAGE = Object.freeze({

server/recv.js

@@ -26,6 +26,7 @@ function handle_event(session, event) {
         }
 
         case EVENT.IMAGE:
+        case EVENT.IMAGE_MOVE:
         case EVENT.UNDO: {
             storage.put_event(event);
             break;      

server/send.js

@@ -21,7 +21,8 @@ function event_size(event) {
             break;
         }
 
-        case EVENT.IMAGE: {
+        case EVENT.IMAGE:
+        case EVENT.IMAGE_MOVE: {
             size += 4 + 2 + 2; // file id + x + y
             break;
         }

server/serializer.js

@@ -51,7 +51,8 @@ export function event(s, event) {
             break;
         }
 
-        case EVENT.IMAGE: {
+        case EVENT.IMAGE: 
+        case EVENT.IMAGE_MOVE: {
             u32(s, event.image_id);
             u16(s, event.x);
             u16(s, event.y);